\begin{tikzpicture}
    \draw (-0.5, -0.5) -- (-0.5, 3.5);
    \draw (3.5, -0.5) -- (3.5, 3.5);
    \foreach \x/\y/\txt/\name in {
        0/0/a_3/a3,   0/1.5/a_2/a2,   0/3/a_1/a1,
        1.5/0/b_3/b3, 1.5/1.5/b_2/b2, 1.5/3/b_1/b1,
        3/0/c_3/c3,   3/1.5/c_2/c2,   3/3/c_1/c1,
     } {
        \node (\name) at (\x, \y) {$\txt$};
    }
    \draw (a1) -- (b2) -- (c3);
    \draw [red] (a2) -- (b3) -- +(0.5, -0.5) arc (225:405:1.5) -- (c1);
    \draw [blue] (a3) -- +(1, -1) arc(225:405:1.6) -- (c2) -- (b1);

    \draw [dashed, blue] (a1) -- +(-1, -1) arc(135:315:1.5) -- (b3) -- (c2);
    \draw [dashed, red] (b1) -- (a2) -- +(-0.5, -0.5) arc(135:315:1.6) -- (c3);
    \draw [dashed] (c1) -- (b2) -- (a3);

    \node at (-1.2, -1) {$(-)$};
    \node at (4, -1) {$(+)$};
\end{tikzpicture}
